Gas turbine engines are used as the primary power source for many types of aircraft. Most turbine engines include rotating components such as a fan, a compressor, and a turbine. The rotating components may be clamped together either by a tieshaft or bolted flange joints to form a rotor group. To support the rotor group, two or more bearing assemblies may be mounted thereto. Specifically, the bearing assemblies may include an inner race component that is disposed on a shaft of the rotor group, an outer race component spaced apart from the inner race component, and a bearing or other roller element disposed therebetween.
The bearing assemblies are typically lubricated with a liquid, such as oil. In this regard, the bearing assemblies are mounted adjacent openings formed in the shaft that communicate with passages that receive the oil from an oil source. To maintain the oil within a certain portion of the shaft, the interior of the shaft is typically sealed with a plug. In one example, the plug is a disk that has an O-ring disposed on its outer periphery. The disk blocks the oil flow, while the O-ring seals against the inner surface of the shaft. In another example, the plug is a disk having a tapered flange extending axially therefrom. This type of plug is typically press fit into the shaft such that the disk outer periphery and the tapered flange contact and seal against the shaft inner surface.
Although conventional plugs operate adequately, they suffer from drawbacks in some circumstances. For example, plugs including O-rings may not suitably seal the shaft, if the rotor group is exposed to high temperatures (e.g., temperatures in excess of 230° C.). In these cases, a tapered flange plug may be employed; however, if the shaft inner surface does not have a substantially smooth surface finish, such as when the shaft has been shot-peened to improve shaft fatigue strength, oil may leak between the plug outer surface and the shaft inner surface.
Accordingly, there is a desire for improved seals and methods for sealing a shaft. It would be desirable for the seal to be capable of sealing the shaft with minimal leakage, even if the shaft is exposed to high temperatures. Additionally, it would be desirable for the seal to be capable of sealing a shaft having an inner surface that may not have a substantially smooth surface finish. Moreover, it would be desirable for the seal to be capable of replacing existing seals.